JPH068426B2 - lubricant - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention includes, for example, between a brush and a commutator of a small motor used in a tape recorder, a video tape recorder, etc., an up / down contact, a slide switch, a relay,
The present invention relates to a lubricant for achieving long-term performance maintenance of various electrical contacts such as connectors and / or sliding parts.

[Conventional technology]

It has been conventionally known that, in various electric contacts and / or sliding parts, foreign matter is formed and accumulated in those parts over time during its operation. These foreign substances sometimes occur due to electric sparks or wear of sliding parts, and accumulate over time, resulting in electrical equipment having electrical contacts and / or sliding parts such as small motors, vertical contacts, slide switches. , Relays, connectors, etc.
As a result, the function may be destroyed.

This will be explained by taking a small motor as a typical example which has the largest number of contact opening / closing times and also has a sliding portion.

A brush and a commutator are incorporated in a small motor, and these brushes are roughly classified into two types.
One of them is a conductive material having elasticity such as copper, beryllium copper, copper-titanium alloy, phosphor bronze, thin plate or wire made of nickel silver and a noble metal or its alloy (eg Au, Pd, P).
It has a structure in which materials such as t, Ag, Cu, etc.) are clad or spot welded together.
The other is a sintered carbon brush (for example, carbon, Ag carbon, Cu carbon, AgCu carbon, and SiC, MoS ₂ , P
b, a brush mixed with an epoxy resin as an additive) is joined by means of a conductive adhesive, spot welding, or caulking method.

When operating in a small motor with these brushes,
That is, when the commutator rotates, the commutator segment and the brush sliding part that slide with each other generate electrical sparks due to the intermittent contact points, and electrical noise is generated with the generation of the electrical sparks. Wear and welding occur on the segments and the sliding parts of the brush. In addition, unnecessary vibration is generated in the brush sliding part during rotation of the commutator, which also causes abnormal welding on the contact surface of the brush sliding part with respect to the commutator segment, resulting in the generation of foreign matter due to spark generation. Often happens.

When the above-mentioned welding or foreign matter is generated, these further rub against the commutator segment and the brush sliding portion to cause scratches, and chips or wear debris generated by this rubbing are generated in the gear part between the commutator segments. Puddle,
The commutator segments are electrically connected to each other, causing rotational instability. In addition, the surface roughness of the brush sliding part and the commutator segment becomes large, which causes the vibration of the brush to become large, which further promotes the generation of electric sparks, which further promotes abnormal wear and the generation of foreign matter. This will result in a decrease in motor performance such as an increase in noise and a deviation in the commutation position.

Generally, the material of the commutator segment is made of a noble metal alloy such as Au, Pd, Ag (for example, alloys such as AgCu, AgCd, AgCuCd, AgCuTi). On the other hand, when the brush is made of the above-mentioned noble metal or its alloy, the surface energy is high, and since the commutator segment and the brush are made of substantially the same material, scratches are likely to occur on the mutual sliding contact surfaces. Further, even in the case of the brush made of only carbon as described above, although the sliding resistance is smaller than that of the noble metal alloy brush, the wear due to electric spark is large, and due to impurities such as SiO ₂ mixed in carbon. Risk of scratches. Further, the carbon brush combined with the noble metal has the same drawbacks as the above-mentioned noble metal alloy brush.

Regarding abnormal wear and welding of the commutator and the sliding portion of the brush, according to the literature etc., an atmosphere of unsaturated aromatic hydrocarbon exists near the electrical contact and / or the sliding portion,
When adsorbed to these, foreign substances called black matter (a mixture of carbon generated by the decomposition of these and abrasion powder generated between the brush and the commutator segment) are generated.

This is because when the unsaturated aromatic hydrocarbon (for example, toluene, styrene, etc.) is incompletely burned, a large amount of carbon is produced, and the carbon becomes relatively dense and hard. When this carbon is generated, that is, when the carbon is properly attached to the brush and the commutator segment, the wear itself of the brush is reduced. However, the formation of foreign matters by the carbon produced from such unsaturated aromatic hydrocarbons has a drawback of increasing wah-flutter of a small motor during long-term use.

[Problems to be solved by the invention]

In the example of the small motor mentioned above, the brush and the commutator are worn by the sliding of the brush and the commutator, the welding is generated, the abrasion damage caused by this, the deterioration of the motor performance due to the mechanical wear and the shortening of the life, and the vertical contact structure The consumption and welding of electrical contacts and sliding parts of electrical connection structures such as a dynamic switch, a relay, or a slide switch having a sliding contact structure, a connector, and the like are major drawbacks of these devices.

Accordingly, the present invention resides in overcoming the drawbacks of various electrical contacts and / or slides as described above, and providing a lubricant therefor.

[Means for solving problems]

The present invention relates to 1,6-hexanediol and / or 2-
A lubricant used for electrical contacts and / or sliding parts made of ethyl-1,3-hexanediol.

The 1,6-hexanediol used in the present invention has a melting point of 4
2.8 ℃, boiling point 760mmHg 208 ℃, 10mmHg 13
It is a substance at 4 ° C, and 2-ethyl-1,3-hexanediol is an oily liquid with a boiling point of 760 mmHg and 244.2.
The substance has a temperature of 163 ° C at 50 mmHg and 129 ° C at 10 mmHg.

The above-mentioned 1,6-hexanediol and 2-ethyl-
According to the present invention, 1,3-hexanediol can be used alone or as a lubricant by mixing both.

In using the lubricant according to the present invention, these lubricants may be directly applied to the electric contact and / or the sliding portion as described above, but it is not always necessary, but rather as described below. Preference is given to using.

For example, the above-mentioned lubricant according to the present invention is impregnated into felt, sponge or the like, and this is fixed or adhered near the electrical contacts and / or sliding parts as described above. In this case, the lubricant is gradually evaporated from the lubricant-impregnated material to create an atmosphere of the lubricant at the electric contact and / or the sliding portion. For this purpose, the electrical contacts and / or the sliding parts are enclosed in a casing. The casing does not necessarily need to be airtight, but it is preferable to have a structure that is as airtight as possible.

For example, for a small motor, the lubricant impregnated material according to the present invention may be adhesively fixed to a part of the motor case, for example, a bracket or a brush fixing member. Alternatively, if it is possible to impregnate the material forming the electrical contact and / or the sliding portion, it may be impregnated.

In any case, the atmosphere of the lubricant is created in the equipment having the electrical contacts and / or the sliding parts, that is, in the casing.

[Action]

The lubricant of the present invention is, of course, applied to the electrical contact and / or the sliding portion directly, as well as the electrical contact and / or the sliding portion as described above.
Or, when they are present near the sliding parts and an atmosphere of the above-mentioned lubricant is formed around them, the lubricant is adsorbed on their surface to form a thin film, which improves their lubricity and Reduce wear due to sliding and formation of foreign matter due to electric sparks.

The lubricant of the present invention, when an electric spark is generated at an electric contact and / or a sliding portion, for example, a contact portion of a brush and a commutator segment of a small motor, incompletely burns like the unsaturated aromatic hydrocarbon described above. , Generate carbon. However, unlike the carbon produced from unsaturated aromatic hydrocarbons, the carbon produced by the incomplete combustion of the lubricant of the present invention is relatively soft, and since the amount of carbon produced is also small, such carbon as the above-mentioned black matter. No abnormality such as conduction between the commutator segments occurs, and therefore, wow-flutter of the motor is not increased.

Also, in the atmosphere around the electrical contacts and / or the sliding parts,
Even when the lubricant according to the present invention and the above-mentioned unsaturated aromatic hydrocarbon coexist, there is little or no black matter produced by combustion of the above-mentioned unsaturated aromatic hydrocarbon. Since this is a polar group contained in the lubricant according to the present invention, it is adsorbed preferentially and strongly to the electric contact and / or the sliding portion over the above unsaturated aromatic hydrocarbon, which causes the adhesion and accumulation of the black matter. It is thought to be to prevent.

〔Example〕

 The present invention will be described below with reference to examples.

Example A polyester felt was washed and degreased with fluoroethylene, and 1,6-hexanediol (Experiment 1), 2-ethyl-1,3-hexanediol (Experiment 2), 1,6-hexanediol and 2- Ethyl-1,3
Hexanediol (50:50) mixture (Experiment 3) was impregnated and each was adhered to a bracket in a small motor to create an atmosphere of each of the above lubricants in the motor.

For comparison, the same felt as above was added to styrene monomer (Experiment 4) or toluene (Experiment 5), respectively.
Were also impregnated with each other, and these were also adhered to the brackets in the small motors to form respective atmospheres.

Further, as another comparative experiment 6, nothing was used, and a normal small motor in the air atmosphere was also used.

The small motor used had an outer diameter of 30 mm, a height of 25 mm, and a rated output of 0.1 W, and was operated at 4.2 V DC and 25 mA. The results are shown in Table 1.

From the above data, it is clear that in the motor provided with the lubricant atmosphere of the present invention (Experiments 1, 2 and 3), the carbon brush is much less worn than in Experiment 6. When compared with the styrene monomer and toluene atmospheres (Experiments 4 and 5), there was no significant difference in the amount of wear of the carbon brush, but in the reduction of wow and flatter after 300 hours of operation, the lubricant of the present invention was very excellent. You can see that In Experiments 4 and 5, the amount of wear of the carbon brush itself can be reduced,
Combustion of styrene and toluene resulted in reduced motor performance and increased wow and fratter.

Further, the commutation waveform diagrams of the motors of Experiments 1 to 6 are shown in FIGS. 1 to 6.

Figure 1 shows the case of the motor of Experiment 1, + 60 ° C, 5% RH
Fig. 2 is a rectified waveform diagram before the test in Fig. 2 and after 1500-hour operation test, Fig. 2 is the same rectified waveform diagram of Experiment 2, Fig. 3 is the same rectified waveform diagram of Experiment 3, and Fig. 4 is 100 hours of Experiment 4. FIG. 5 is a rectified waveform diagram after an operation test, FIG. 5 is a rectified waveform diagram after an operation test of 300 hours in Experiment 5, and FIG. 6 is a rectified waveform diagram after an experiment time of 300 hours in Experiment 6.

By comparing FIGS. 1 to 6, it can be seen that the motor using the lubricant of the present invention maintains its excellent performance for a long time.

〔The invention's effect〕

The lubricant of the present invention can reduce wear on electrical contacts and / or sliding parts, reduce the production of foreign matter, and reduce wow-flutter in small motors. The performance of can be maintained for a long time. Therefore, it has an excellent effect that the life of each device can be extended.

[Brief description of drawings]

1 to 6 are rectification waveform diagrams of the small motors of Experiments 1 to 6 shown in Examples.

Claims (1)

[Claims] 1. A lubricant comprising 1,6-hexanediol and / or 2-ethyl-1,3-hexanediol.